How can a single keystroke create 2 KeyPress events?

cVoronoff

6/21/23, 4:16 AM

For no apparent reason, some keys on my keyboard started behaving strange. Most notably on the numpad I would get 2 numbers or a number and a sign with a single keystroke. Used command xev on the terminal and saw that some keys had 2 events for a single keystroke.

Here is an example of the results I got pressing key '9' on numpad.

KeyPress event, serial 37, synthetic NO, window 0x2800001,
    root 0x789, subw 0x0, time 8174693, (1195,543), root:(1245,662),
    state 0x10, keycode 114 (keysym 0xff53, Right), same_screen YES,
    XLookupString gives 0 bytes: 
    XmbLookupString gives 0 bytes: 
    XFilterEvent returns: False

KeyPress event, serial 37, synthetic NO, window 0x2800001,
    root 0x789, subw 0x0, time 8174694, (1195,543), root:(1245,662),
    state 0x10, keycode 81 (keysym 0xffb9, KP_9), same_screen YES,
    XLookupString gives 1 bytes: (39) "9"
    XmbLookupString gives 1 bytes: (39) "9"
    XFilterEvent returns: False

KeyRelease event, serial 37, synthetic NO, window 0x2800001,
    root 0x789, subw 0x0, time 8174912, (1195,543), root:(1245,662),
    state 0x10, keycode 114 (keysym 0xff53, Right), same_screen YES,
    XLookupString gives 0 bytes: 
    XFilterEvent returns: False

KeyRelease event, serial 37, synthetic NO, window 0x2800001,
    root 0x789, subw 0x0, time 8174923, (1195,543), root:(1245,662),
    state 0x10, keycode 81 (keysym 0xffb9, KP_9), same_screen YES,
    XLookupString gives 1 bytes: (39) "9"
    XFilterEvent returns: False

Also, during the day the combination of events would change. I couldn't see a pattern, but it was mostly the numpad, arrow and special characters keys that had this problem. I made no updates/upgrades prior to this.

I have a X11 driver, and tried reinstalling it, with no luck. I also don't think it is a hardware problem. How do I solve this? Or at least, what should my next step be?

Any help will be appreciated!

0 + 0

xorg

keyboard

David

6/21/23, 8:23 AM

Have you tried a different keyboard? Have you booted from a live media and seen if it does it there as well?

cVoronoff

6/21/23, 5:22 PM

@David Different keyboard, yes. Same problem but on different keys. Hadn't thought of live media. Will try now.

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: How can a single keystroke create 2 KeyPress events?

TH: การกดแป้นเดียวสร้าง 2 KeyPress เหตุการณ์ได้อย่างไร

RO: Cum poate o singură apăsare a tastei să creeze 2 evenimente KeyPress?

RU: Как одно нажатие клавиши может создать 2 события KeyPress?

VI: Làm cách nào một lần nhấn phím có thể tạo ra 2 sự kiện KeyPress?

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